天津市基坑抽排地下水量计量研究

基于天津工程地质特点和水文地质特点,通过对天津市内多个基坑降水工程全方位、全过程的监测,运用不同测量方法,通过抽样与全面对比,研究了基坑疏干井与降压井抽水量变化关系,并结合已有工程实例,确定了不同类型基坑适用的降水水量计量方式,取得了基坑降水水量计算的经验公式。同时,根据不同计量方式下抽水过程中电量水量监测数据,总结了气泵降水和潜水泵降水抽水量与耗电量之间的关系。根据典型工程的测量结果并结合理论推导,提出3种基坑工程地下水抽排量估算方法,即井流量计算法、体积计算法和电量推测法。

Measurement of groundwater dewatering in excavations in Tianjin

Based on the characteristics of engineering geology and hydrogeological characteristics in Tianjin, multiple excavation dewatering projects are monitored comprehensively in the entire process. Using different measurement methods, the pumping volume change relationships of excavation dewatering well and step-down well are studied through the sampling and comprehensive comparison. Combined with the existing engineering examples, the measurement methods and methods of precipitation water for different types of excavations are determined, and the empirical formula for calculating the precipitation water volume of excavations is obtained. At the same time, according to the monitoring data of water quantity in the process of pumping in different metering methods, the relationship between pumping water pumping and submersible pumping water pumping capacity and power consumption is summarized. According to the measured results of typical engineering and theoretical derivation, three methods for estimating groundwater pumping displacement in excavation engineering are proposed, namely well flowmeter method, volume calculation method and electricity estimation method.